It is the objective of the research carried out under this program/project to explore new avenues for improved or new materials to be used as dental restoratives by employing the latest theoretical methods and experimental techniques available to materials scientists. The efforts carried out during the past year can be listed under three headings: 1. Strength and structure of Dental Amalgams; 2. Corrosion of Dental Alloys; 3. Crystallography of Biomaterials. It is the purpose of this request to secure the orderly conclusion of a research effort which has been supported by the Nation Institute for Dental Research for almost ten years. The completion of our present research would also permit the undelayed start of research in dental materials through new grants in areas different from the present projects, or with a different emphasis or goal.